The Thirlwall Inquiry's findings into how Lucy Letby was able to repeatedly murder and harm babies at a hospital neonatal unit will be released on 15 September 2026 in Liverpool. The public inquiry examined the actions and decisions of managers at the Countess of Chester Hospital during the period when Letby worked there, focusing on whether earlier intervention could have prevented deaths and injuries.
Letby, now 36, is serving 15 whole-life prison sentences for murdering seven babies and attempting to murder seven others, including one infant she tried to kill twice. The inquiry, chaired by Lady Justice Thirlwall, was not tasked with re-examining her guilt or the safety of her convictions. Instead, it investigated how hospital leadership handled concerns raised about the neonatal nurse and whether action could have been taken sooner to remove her from the unit.
The investigation focused on events between 2015 and 2016 while Letby worked in the neonatal unit. According to BBC analysis, the report is expected to conclude there was a "total failure of processes" around patient safety at the hospital. A key question the inquiry examined was whether any babies might have survived or avoided harm if hospital management had acted earlier to remove Letby from her position.
Letby was moved from the neonatal unit to administrative duties in July 2016 after consultants raised concerns about her with the hospital's executive team. However, the inquiry investigated whether warning signs should have prompted action much sooner—for instance, in June 2015 after three babies died in rapid succession. The investigation involved six months of evidence-gathering and review of thousands of documents, costing more than £18.5 million.
What is the inquiry expected to find?
The report is anticipated to identify significant safeguarding failures at the hospital and recommend systemic changes across the NHS. The inquiry's official website confirmed the 15 September 2026 publication date on 27 August 2026, with Lady Justice Thirlwall expected to deliver remarks at the public release event in Liverpool, which will be streamed live. Core participants in the inquiry will receive advance sight of the report before the public announcement.
How might this affect Lucy Letby's legal position?
The Criminal Cases Review Commission (CCRC)—the only body with power to refer Letby's case back to the Court of Appeal—has indicated it will scrutinize the inquiry report closely. Letby has been denied permission to appeal against her convictions twice previously. Her defence lawyer Mark McDonald has submitted what he describes as "nearly 30 expert reports to the CCRC really undermining the whole safety of the convictions," claiming this represents more evidence than "any other case" in the CCRC's history. McDonald stated:
If she is innocent, as I believe, as 30-odd experts believe, then everything that has gone before the inquiry and every recommendation has operated on the wrong premise.
However, McDonald's defence team faced a significant setback when two experts withdrew their support. Prof Geoff Chase from the University of Canterbury in New Zealand and chemical engineer Helen Shannon quit the team after determining that some evidence being advanced was inconsistent with available scientific data. McDonald told night he was "sad that they've gone" but maintained those experts still believed "Lucy Letby is innocent," suggesting they disagreed with his team's approach rather than the core claim of innocence. He added:
What they're saying is: 'We think our argument's better than your argument and therefore we're coming out of it'.
What is the timeline of the inquiry?
The Thirlwall Inquiry began in September 2024, with the evidence and submissions phase concluding in March 2025. The findings were originally scheduled for publication in November 2025 but have been delayed multiple times. One delay pushed the publication date to after Parliament's summer recess, with the final date now confirmed as 15 September 2026. These postponements have had cascading effects on related proceedings: the inquests into the babies' deaths have been rescheduled until May 2027.
What criminal investigations are ongoing?
In July 2025, three former senior staff members at the Countess of Chester Hospital were arrested on suspicion of gross negligence manslaughter. These individuals worked on the hospital's senior leadership team between 2015 and 2016 and remain on police bail. The arrests followed an investigation into potential corporate manslaughter opened by Cheshire Police in 2023, which was expanded in March 2025 to include gross negligence manslaughter charges. One of the three former staff members was re-arrested in April on suspicion of perverting the course of justice, though no charges have been filed in any of these cases.
What is the broader context?
The inquiry's establishment and scope reflect lessons from a previous healthcare scandal. Approximately 25 years before Letby's crimes, nurse Beverley Allitt committed similar offences on a children's ward in Grantham, Lincolnshire. The Thirlwall Inquiry was established with two key objectives: to seek answers for the families of victims and to ensure that institutional lessons are learned to prevent similar failures in the future.
What happens next?
The final report will be published in Liverpool on 15 September 2026, with Lady Justice Thirlwall delivering public remarks at the event. The CCRC is expected to give the report detailed consideration as it reviews any future applications from Letby's legal team. The inquests into the deaths of the babies will proceed in May 2027, providing another forum for examination of the circumstances surrounding their deaths.
